Monday, April 30, 2018

Looking for 2 5/8" Aluminum Square Bar

Odd size.  Trying to avoid machining 2.75" down.   Right now I use 2.75" acetal that I run through a planer.

I had thought of using shims.  And when I looked for .100" thick aluminum, I found it!  (The local metals store does not have it.)  2.5" bar with 2 .100" shims gives 2.700".  I need to slide into a 2.75" inside square tube, so this will likely be a epoxy the shims on, tap it into the tube, then screw through the tube and shims into the 2.5" bar.


  1. 1) Buy a bigger mill or mill-drill.
    2)Consider laminating flat stock or adding it to bar stock to get the dimension(s) you need. (screw it together).
    You might do steel square tubing with aluminum facing, or some other combo.

  2. Will: My first thought was putting a shim to fill in the gap between 2.5" and the 2.75" interior. But the thicknesses on aluminum sheet seem to go .190" to .250" with nothing between. .190" means a .06" gap, which is not likely to be very tight, and .250" is too tight. I might use .080" (one on each side) but that still gives me a .09" gap. I may have to hunt for something .1". This still leaves .05" which is okay since I will be using screws to hold it in place.

  3. Had to be out there: .100" thick. One on each side gets me .05" gap or .025" on each side. That should be tight enough to be barely fitting. I will still screw through the shims into the 2.5" bar.

  4. IIRC, 1/8" [0.125"] aluminum should be available. Might be plus or minus a couple thousand, as gauge dimensions vary slightly depending on the material, for some unremembered reason.